Addictions

Question 1

Which opioid receptor causes most of the adverse effects?

Answer 1

Mu

Question 2

Opioid toxidrome

Answer 2

Mental status: euphoria, sedated, coma
Vitals: decrease in RR/temp/BP/HR
Miosis
Apnea/resp depression, pulmonary edema
Reflexes: normal/hypo

Question 3

Respiratory depression due to opioids

Answer 3

Mu2 subtype located in medulla
Decreases ventilation by decreasing sensitivity of medullary chemoreceptors to hypercapnia and decreasing ventilation response to hypoxia
Results in no stimulus to breathe
Also suppresses cough center in medulla

Question 4

What parts of the resp depression can you/can you not develop tolerance to?

Answer 4

Can develop tolerance to the loss of hypercapnic drive, but never to the loss of hypoxic stimulus

Question 5

Naloxone

Answer 5

Opioid antagonist
IV, IM, intranasal, SC, ETT, inhaled
High affinity for mu receptor
2 min onset of action, lasts for 20 mins - 2 hours
Indication: significant CNS or resp depression (need 50% mu reversal for effect)
Can cause withdrawal

Question 6

Signs and symptoms of opioid withdrawal

Answer 6

Irritability
GI upset
Muscle and joint pain
Piloerection
Dilated pupils
Sweating
Anxious

Question 7

How long should you monitor someone after giving naloxone at doses of

1. < 0.9 mg
2. > 0.g mg

Answer 7

1. 2 hours

2. 4-6 hours

Question 8

Is morphine indicated as a treatment for acute migraine?

Answer 8

No!

Question 9

Drugs of abuse act on what structure of the brain?

Answer 9

Nucleus accumbens

Causes DA release in the VTA and prefrontal cortex

Question 10

Criteria for opioid use disorder (dont need all of them)

Answer 10

Cravings
Withdrawal
Tolerance
Unable to cut down
Use despite harm
Hazardous situations
Failure to meet obligations
Reduced social, occupational, and/or recreational activities

Question 11

Buprenorphine/naloxone

Answer 11

Ciboxone
First line for opioid use disorder
Available as sublingual tablets
Semi synthetic opioid (partial my agonist)
Low intrinsic receptor activity (ceiling effect)
High receptor affinity (blocks other opioids, precipitate withdrawal in opioid tolerant)
Slow dissociation (long duration of activity)

Question 12

Methadone

Answer 12

Second line when ciboxone is not an option
Mu receptor agonist
Non competitive NMDA antagonist (mitigates opioid induced tolerance)
Available as tablets and liquid

Question 13

What is the initial rate of a naloxone infusion?

Answer 13

0.1 mg IV or 0.4 mg IM

Every 3 mins PRN x2